A coupling generally comprises two connecting members of same structure, and a cushioning member disposed between the two connecting members. Each of the connecting members generally comprises a base and a plurality of connecting arms extending to the other connecting member. The cushioning member typically comprises an annular ring and a plurality of cushioning arms extending radially outwardly from the outside of the ring. Each of the cushioning arms is sandwiched between two connecting arms extending from a respective one the connecting members. The annular ring is surrounded by the connecting arms. One of the bases is connected to a motor shaft, and the other one is connected to an output shaft, so that output torque is transmitted from the motor shaft to the output shaft. However, the axial length of the coupling is large since each of the connecting members comprises a base.